1. Field of the Invention
The present invention relates to counterweights and, more particularly, to an adjustable counterweight for use in construction vehicles.
2. Description of Related Art
Counterweights are used in construction machines such as hydraulic shovels and movable cranes to improve traction and stability by holding a front end of the machine more stable when using the mechanism on the front end (i.e., backhoe or crane) and during maneuvering of the machine. FIG. 1 shows a prior art counterweight 10 located in a rear end 14 of a construction vehicle 12. The counterweight 10 typically has a pre-determined weight and size depending on the size and weight of the construction vehicle. Generally, construction vehicles have a maximum load or weight limit that depends on both the size of the construction vehicle and the weight of the counterweight. The maximum load limit of the construction vehicle can be varied by varying the weight of the counterweight. In certain situations where space is limited (e.g., inside a factory or warehouse), it may be necessary to use a construction vehicle at or around its maximum weight limit. For example, it may be easier to use a small crane at or around its maximum load limit inside a warehouse or factory, than to use a larger crane and have to remove portions of a roof or relocate existing equipment in order to fit the larger crane. In this situation, it may be necessary to increase the weight of the counterweight thereby increasing the maximum load limit to stabilize further the crane during use. This can be accomplished by removing the existing counterweight from the back of the crane and replacing it with a larger and/or heavier counterweight. The purchasing, transporting and/or storing of additional counterweights not only increases the cost of the construction vehicle, but requires a large storage area for this additional piece of equipment.
Therefore, it is an object of the present invention to provide an adjustable weight plate arrangement adapted to mount within a prior art counterweight of a construction vehicle in order to increase the maximum weight limit of the construction vehicle.